Today, dental and medical professionals use many instruments that are controlled by control systems. For example, surgical cutting instruments, ultrasonic dental scalars, endoscopic tools, irrigation and aspiration tools, dental drills, air polishers, other low speed hygiene dental instruments, and dental prophylaxis units can be activated with foot control systems. The foot switch system typically includes a foot controller device that is placed on the floor within easy reach of the practitioner. The foot switch is used to activate a dental/medical apparatus, which includes a base operating unit, which usually is countertop-mounted and adjacent to the dental work area. The available foot pedals include both “hardwired” systems and wireless foot control systems. The base unit is activated by depressing the foot pedal, typically with a foot, which initiates communication with the base operating unit. The base operating unit is then in communication with the instrument, usually a dental instrument.
Some conventional foot switches include multi-positioned or multistaged switches. An operator depresses the pedal of the foot switch to a certain position, which causes the medical/dental apparatus to operate in a specific mode. The particular operational mode is based on the position of the switch. For example, with a two-position switch, a dental practitioner can depress the pedal to a first position so that water flows through the dental instrument for rinsing the teeth of the patient. Then, the pedal of the foot switch can be depressed to a second position so that a cleaning spray flows through the dental instrument for spraying the teeth. Such control systems provide several advantages.
First, a foot pedal device is easy to use and efficient. The dental/medical professional can activate the instrument attached to the base unit by simply depressing the foot pedal with his or her foot. Secondly, the dental/medical practitioner's hands are kept free when working with a foot pedal device. The practitioner thus can handle other instruments and accessories while treating the patient. The practitioner is better able to concentrate on performing the needed dental/medical procedure. Thirdly, as mentioned above, some conventional foot pedals are used in wireless systems, which do not run a connector cable between the foot pedal and base unit. These wireless foot pedals are used to remotely activate the base unit and attached dental/medical instruments. Many dental/medical operatory rooms contain numerous long cords, cables, wires, and the like which can become entangled easily. The entangled cords and cables take up space and may cause potential safety hazards. A wireless foot pedal system helps minimize some of these hazards.
Foot pedals can have a wide variety of structures. One two-position foot pedal of particular interest is set forth in the U.S. Pat. No. 7,439,463 to Brenner et al. issued Oct. 21, 2008, assigned to the Assignee of the present invention, and incorporated herein by reference in its entirety. The foot pedal device includes a base plate for supporting the foot pedal device on the floor, a central housing attached to the base plate, an upper cover mounted on the housing, and a connecting collar attached to the upper cover for retaining a cover on the housing while allowing the cover to move upwardly and outwardly relative to the housing. The central housing contains the first electrical switch for transmitting a first signal of the apparatus, a second electrical switch for transmitting a second signal to the apparatus, and an actuator assembly for activating the switches. The actuator assembly includes (i) an actuating plunger capable of moving in upward and downward directions, (ii) a first switch activator tab, and (iii) a second switch activator tab. An operator depresses the upper cover with his or her foot so that the cover engages the actuating plunger. As force is applied to the plunger, the plunger moves downwardly to a first position, where it engages the first switch activator tab, thereby causing the first switch to be activated. A second force applied to the plunger causes the plunger to move downwardly to a second position, where it engages a second switch activator tab, thereby causing the second switch to be activated. The foot pedal further includes a primary spring and a secondary spring. Downward pressure by the foot on the foot pedal causes the first switch to be activated. However, the primary spring resists the downward pressure thereby causing resistance that provides a tactile feel to the foot pedal. Further downward pressure causes a second switch to be activated while also causing compression of the secondary spring. This additional resistance provides further tactile feel to the operator that signals to the operator a second mode of operation has been activated. The device contemplates both wireless operation and wired operation.
Bresnahan et al., U.S. Pat. No. 4,041,609 discloses a foot pedal unit for controlling the operation of dental equipment, particularly air turbine dental instruments. The foot control unit includes a triangular-shaped base, a body portion that is supported by the base, and a removable cover. Three pivotal pedals project radially from the body portion of the foot switch in the form of a spider-like configuration. The pedals are arranged at evenly spaced positions around the circumference of the base. Each pedal includes a foot-engageable shoe connected to a pedal support member. A dentist may depress any of the pedals, and this action is transmitted to an actuator member, which also has a three arm spider-like configuration. The actuator causes a vertically movable plunger to be depressed and a control unit in the foot switch is activated. An electrical cable extending from the foot control unit to the dental instrument is used to transmit the switching signal.
Jones et al., U.S. Pat. No. 4,114,275 discloses a foot pedal for controlling the flow of compressed air to an air-driven dental instrument. The foot pedal includes a diaphragm therein for forming an air-sealed chamber, which reduces in volume upon depression of the foot pedal. As the foot pedal is depressed, air is conveyed through an air tube to an air modulating, regulator valve that is positioned away from the foot pedal device. The valve controls the flow of compressed air to the dental instrument and drives the dental instrument. Alternatively, the system can include a diaphragm-operated electrical switch that is positioned away from the foot pedal for electronically controlling the flow of air to the dental instrument.
Matsui, U.S. Pat. No. 4,417,875 discloses a foot pedal for controlling the rotational speed of an air turbine dental instrument. The foot pedal is designed such that the front part of the pedal is used for controlling high-speed rotation of the dental instrument and requires a relatively small amount of foot pressure, while the rear portion of the pedal is used for controlling low-speed rotation and requires a relatively high amount of foot pressure.
Lee, U.S. Pat. No. 5,132,498 discloses a foot pedal comprising a base covered with an upper cover and a press member. The foot pedal houses a pressure-contact switch, a pivoting rotary-type actuating member, and compression spring. The press member is pressed down in response to a foot-pressing action. This causes the actuating member to rotate downward so that a hooked portion of the actuating member is pressed against a cylindrical press button, thereby activating the foot pedal.
Warrin et al., U.S. Pat. Nos. 5,125,837 and 5,419,703 disclose an ultrasonic dental scaler unit having a dental instrument and scaling insert that can be used for scaling teeth and providing therapeutic lavage solutions to periodontal pockets in the mouth. The dental scaler unit includes a foot pedal, which is connected to the base unit by an electrical cable. The scaler unit further includes a dental instrument, which is connected to the base unit by a conduit containing electrical wires and a tube for cooling water. The base unit includes a switch that can be thrown to a first or second position. The foot pedal also can be depressed to a first or second position. The positions of the base unit switch and foot pedal make it possible for the practitioner to use the apparatus for scaling only, lavage only, or simultaneous lavage and scaling.
Jovanovic et al., U.S. Pat. No. 5,754,016 discloses an ultrasonic dental scaler system having a base unit, which is connected by a cable to a foot pedal. The scaler dental instrument, which is connected to the base unit, includes a feedback coil for controlling the amplitude and vibration of the magnetostrictive scaling insert. The amplitude and frequency of vibration of the tip of the scaling insert can be continuously adjusted to maintain constant scaling power. The foot pedal is connected to a boost enabler in the base unit by a connector cable. The foot pedal can include first and second electrical contact positions, where the second position provides a temporary boost in power to the dental instrument.
Beerstecher, U.S. Pat. No. 6,866,507 discloses a foot pedal for controlling the operation of a dental apparatus having a multifunctional dental instrument. The foot pedal includes a base plate and a relatively movable cover plate. A space between the base plate and cover plate forms a fluid tight hollow cavity. Multiple press switches are arranged in the hollow cavity. The press switches are made from a printed circuitry, which is sandwiched between first and second carrier foils. A signaling line connects the foot pedal to the electronic control systems of the dental apparatus.
Feine, U.S. Pat. No. 6,893,261 discloses a foot pedal for controlling an ultrasonic dental scaler. The foot pedal incorporates the circuitry for controlling the vibrational frequency of the scaling insert and can also provide water and light to a remote head unit. A cable bundle connects the foot pedal to the remote head. The foot pedal housing is connected to a power supply and is additionally connected to a water source. The foot pedal housing can also include a light source such as an argon lamp. The remote head can be attached to a dental treatment chair or it may be carried on the belt of a dentist or dental hygienists.
What would be useful is a wireless, remote foot controller that recognizes the dental instrument in the hands of the dental professional and determines whether it should generate a signal that is responsive to pressure to provide a signal that varies in proportion to the directional movement of the foot controller by the foot, thereby driving a dental instrument in an infinitely variable manner or whether it should be responsive to the directional movement of the foot controller to provide a plurality of discrete signals that are activated by the directional movement of a foot controller by the foot, thereby driving the dental instrument at discrete speeds. Ideally, the foot controller should provide a tactile feel to the user so that the user can obtain a sensory feel of the speed that the hand unit is being driven based on the pressure applied by the user's foot. The foot controller should be in communication with the dental instrument so that the foot controller can determine whether the dental instrument is controlled based on being driven by discrete signals or in an infinitely variable fashion.